We know that people will go very far in the search for more energy and a lot of that time it means pouring in the caffeine. But can too much caffeine too fast be deadly? Tonight, the fda is looking into reports of more than a dozen people whose deaths might be linked to the 5-hour energy drink. And abc's senior national correspondent jim avila has more on these potential caffeine bombs. Reporter: These youtube videos are a manual on what not to do with an energy drink. This is cleary 5-hour energy drink abuse. Chug, chug! Reporter: Videos that anger the founder of the billion-dollar company, that sells 1.5 million 2-ounce bottles of the stuff every day. Don't get crazy. Don't take too much. That would be a really dumb thing to do. If you do dumb stuff, you are going to end up in the hospital. Reporter: And manoj bhargava says that's the only way his little bottle of jolt is dangerous -- abuse. As for today's alarming news of 13 deaths and 33 hospitalizations the last four years, reported to the fda, all claiming to be linked to this product, bhargava says just not true. Is there any risk to a healthy person drinking your product? Not at all. None. Reporter: How much caffeine is really in 5-hour energy? A 2-ounce bottle contains 207 milligrams of caffeine. Equivalent to two 8-ounce cups of coffee. 2.5 red bulls. Or nearly 6 coca-colas. And many doctors say research shows that doesn't tell the whole story. Energy drinks take it to a different level because there are other components, other ingredients, in these drinks that take the caffeine and make it even more potent. Reporter: One of the ingredients in 5-hour energy is taurine, what scientists call a caffeine-potentiating amino acid, or coffee turbo-charged. Kicking up the caffeine dramatically. If you knew you were capable of drinking four cups of coffee over the morning, you probably would feel very different than if you drank four energy drinks. Reporter: How much caffeine does it take to kill a healthy person? About 5,000 milligrams. That's 50 couple of coffee, or 25 shots of 5-hour. Many more than the two bottles a day 5-hour energy recommends. Jim avila, abc news, new york.

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